Objective: The objective of this study was to assess the sonographic findings in renal parenchymal diseases using gray-scale ultrasound in order to classify these diseases. The study design was a cross-sectional one. There were 204 patients who were suspected with renal diseases. They had been scanned with ultrasound to assess the kidneys. The echogenicity, renal cortex and paren-chyma, and cortico-medullary differentiation had been evaluated. Results: The study revealed that the echogenicity of renal parenchyma and cortex increased in all types of renal parenchymal diseases. The cortico-medullary differentiation was mainly disturbed in acute parenchymal disease (69.04%), loss in chronic end-stage parenchymal disease (85%); and there was significant difference (p-value = 0.0001). Conclusion: Ultrasound provided useful and accurate diagnosis of renal parenchymal diseases. In this study, renal parenchymal diseases had been classified into acute, chronic and end-stage renal parenchymal diseases.